Re: tobirama is tobi
That could be so but that still makes no sense because you have no solid proof of them being the same person. Like what these other humans said, he couldn't have been summoned by Edo Tensei if he was still alive. If you were referring to how Hashirama is somewhat infused in Madara, I don't see why Tobirama's DNA shouldn't be infused to Tobi. (Basically for his Space/Time Jutsu) But otherwise, there is no way Tobirama is Tobi...I believe tobirama is partly tobi just like harishima is partly madara. That would explain why Kishi never shows tobiramas jutsus.